Boot into Safe Mode by repeatedly pressing the F8 key after booting until the Startup Options menu appears

Choose to boot into Safe Mode

Start Windows Explorer (or open any folder or open My Computer)

Click Tools

Click Folder Options

Go to the View tab

At the Under hidden files and folders, select Show hidden files and folders and then click the Hide protected operating system files (Recommended) check box to be cleared (unchecked)

Click Yes to confirm these actions

Windows XP show hidden files screen

Go to My Computer > C:\ drive or the drive where you installed your Windows

Click on the System Volume Information folder.If you receive Access denied, please follow these guidelines to get access to that folder: http://support.microsoft.com/kb/309531.
You’re most likely to receive Access denied if your Windows XP is on NTFS and not on FAT32.
If it’s on FAT32, you can continue the steps below.

Open any folder that wasn’t created at the current time, e.g. when you logged into the computer at this session.You can check this by right clicking on the first folder and check its date.The title format of these folders is something like this:

_restore{87BD3667­3246­476B­923F­F86E30B3E7F8}

Open any RP folder in that folder, e.g. RP1, and go to Snapshot.These are called Restore Points. Here is an example of path:

Fix a corrupt registry in Windows 8 or 8.1

Refresh. The Refresh option will not affect your files. Windows 8 will reinstall any applications you installed and create a copy of these applications on your desktop, but backup your data before you do a refresh.

Reset. A Reset option will remove all your personal files and delete any settings or configuration you did on your computer.

Run Automatic Repair

To run Automatic Repair which will attempt to fix a corrupt registry on your Windows 8 or 8.1 system, follow these steps:

Open the Settings panel

Go to General

At the Advanced Startup panel, click Restart now

Windows 8 Advanced Startup

At the Choose an option screen, click Troubleshoot

At the Advanced Options screen, click Automated Repair

Choose an account and login, when prompted to do so

Automatic Repair should now start and your computer may reboot during this process

Windows 8 Advanced Startup screen

Refresh

To perform a Refresh on your Windows 8 or Windows 8.1 system, follow these steps:

Go to the Settings panel

Go to Change PC Settings

Click Update and recovery

Click Recovery

At the Refresh your PC without affecting your files section, click Get started

Follow the instructions to complete the refresh procedure

Windows 8 Recovery Screen

Reset

To do a Reset of your Windows 8 or Windows 8.1 system, follow these steps:

A Reset procedure will erase personal data from your computer. Backup your files before you continue.

Go to Settings > Change PC Settings

Click Update and recovery

Click Recovery

At the Remove everything and reinstall Windows section, click Get started

Follow the instructions to complete the refresh procedure

Windows 8 Recovery Screen

Fix a corrupt registry in Windows 10

Refresh. The Refresh option will not affect your files. Windows 10 will reinstall any applications you installed and create a copy of these applications on your desktop, but backup your data before you do a refresh.

Reset. A Reset option will remove all your personal files and delete any settings or configuration you did on your computer.

Run Automatic Repair

To run Automatic Repair which will attempt to fix a corrupt registry on your Windows 10 system, follow these steps:

Open the Settings panel

Go to Update & Security

At the Recovery tab, click Advanced Startup -> Restart now

Windows 10 Advanced Startup

At the Choose an option screen, click Troubleshoot

At the Advanced Options screen, click Automated Repair

Choose an account and login, when prompted to do so

Automatic Repair should now start and your computer may reboot during this process’

Windows 10 Advanced Startup screen

Refresh

To perform a Refresh on your Windows 10 system, follow these steps:

Go to the Settings panel

Go to Update and Security

Click Recovery

Click Get Started

At the Reset This PC section, click Get started

Click Keep My Files

Follow the instructions to complete the refresh procedure

Windows 10 Recovery screen

Reset

To do a Reset of your Windows 10 system, follow these steps:

A Reset procedure will erase personal data from your computer. Backup your files before you continue.

Go to the Settings panel

Go to Update and Security

Click Recovery

Click Get Started

At the Reset This PC section, click Get started

Click Remove Everything

Follow the instructions to complete the refresh procedure

Windows 10 Recovery screen

Troubleshooting

Registry permissions in Windows XP

In Windows XP (only the Professional version), the permissions of the registry can block you from editing certain keys.